On Saturday 02 January 2010, Bartłomiej Zimoń wrote:> Dnia 2 stycznia 2010 16:56 Daniel Borkmann <danborkmann@googlemail.com> napisał(a):> > Hi Andy,> > > > 2010/1/2 Andy Walls <awalls@radix.net>:> > > Why not:> > >> > > a. write a module that implements a device node that supports poll(),> > > and> > >> > > b. have a user space process select() on the fd for read or exception> > > notification> > >> > > ?> > > > This is, of course, another possible solution that is more "cleaner"> > than the one with the signals.> > Then, your userspace program would have another thread polling for the> > device node. Question is which timeout would be appropriate to be "CPU> > friendly" and to keep notification latency short?> > > > Just need as fast as possible solution and on the other hand acceptable for kernel sources.> Usually programs needs just to disconnect something or set one flag.> Even if program will have no time for this it could be enough just to send this precious info.

Perhaps I don't understand correctly what you're trying to achieve, but at themoment suspend is always started from user space, this way or another, and onthe majority (all?) of the modern distros pm-utils is involved in that.So, why don't you provide a pm-utils hook for your process (like, for example,NetworkManager)?